that可以引导名词性从句、定语从句。that引导名词性从句时(即主语、宾语、表语、同位语从句),在从句中无具体含义,只起连接作用,而且在从句中也不作任何句子成分。
that引导的主语从句,表语从句以及同位语中,that不能省略。
that引导的宾语从句,一般可以省去that,但在下面情况中不能省略。
1、在suggest,order等表示命令、请求、建议等动词后的宾语从句中,不能省。
2、由and或but所连接的两个引导的宾语从句时,第一个从句中的that可以省,第二个从句中的that不能省。
辨析:
that, which
that和which都可引导定语从句,但以下情况引导定语从句的关系代词只能用that不能用which:
1.当先行词是all, everything, nothing, anything, little等不定代词,或被first, last, only, few, much, some, any, no等词修饰时,应该用关系代词that,不用which。
2.当先行词为形容词最高级所修饰时,关系代词用that不用which。
3.当并列的两个先行词分别表示人和物时,要用关系代词that而不用which。
4.在强调句型“It is〔was〕...that〔who〕...”中,只能用that,不能用which。
that可以引导以下从句:
1、用作关系代词,引导定语从句 The only thing that I can do is to have a rest . 我唯一能做的事就是休息。
2、用作关联词,引导名词性从句
That the earth turns around the sun is known to all. 地球围着太阳转这一点是众所周知的。(引导主语从句)
It so happens that I know the man. 碰巧我认识那人。(主语从句)
I will see to it that everything is ready. 我会注意把一切准备妥当的。(宾语从句)
The trouble is that we are short of money.困难就在于我们缺钱。(表语从句)
There is no doubt that he is the best choice for this position. 无疑,他是这一职位的最佳人选。(同位语从句)
3、构成短语,引导状语从句
Bring it nearer so that I may see it better .拿近一点,好让我看清楚些。 ( so that 引导目的状语从句)
She got up early , so that she caught the early bus. 她起得早,所以赶上了早班车。( so that 引导结果状语从句)
In order that everybody should hear him , he spoke loudly. 他大声说话,为了使大家都能听得见。(in order that引导目的状语从句)
Now that they have taken matters into their hands the pace of events has quickened.他们既然已着手自己来处理问题,事态的进展也就加快了。(now that 引导原因状语从句)
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